How to Change Car Batteries

How to Change Car Batteries


Picture this: You hear the slow clanking of your car’s motor, and you see the Check Engine light appear on the dashboard. You determine it’s time to change your car battery, so you purchase a replacement. Now what? The team at BMW of Stratham can help you figure out how to change your car battery!

We’ve created this quick, step-by-step guide about how to change car batteries for drivers in Stratham, Portsmouth, and Exeter, New Hampshire. Read on, then contact our team with any questions.



STEP 1: Grab Your Tools & Find the Battery

How to Change Car BatteriesThe first thing you’ll want to do when replacing the battery is turn off your car and put it in Park. Then, pop the hood to find the battery. Some cars may have the battery in the trunk, so it’s always a good idea to reference your owner’s manual.

On hand, you’ll want to have:

  • The replacement battery
  • A wrench, socket, or pliers
  • Battery cleaner and a wire brush
  • Protective clothing, work gloves, and eyewear

STEP 2: Disconnect Battery Terminals

Before you disconnect the terminals, be sure to put on protective eyewear and work gloves. The battery itself will have two terminals—one positive and one negative—and will often be mounted on a tray. Use your wrench to disconnect:

  • First, the black negative terminal (-)
  • Second, the red positive terminal (+)

It’s essential that the negative terminal be removed first. Be sure the battery terminals do not touch any metal surface.

STEP 3: Remove the Old Battery

How to Change Car BatteriesNext, you’ll want to remove the old car battery, which will be secured with a metal bar or clamp. Use your wrench to loosen the bolts, then carefully remove the battery. Be sure to keep the battery upright to avoid spilling any liquid.

STEP 4: Clean the Battery Cables & Terminals

With the old battery removed, it’s time to clean the cables and terminals using the battery cleaner and a wire brush. If battery cleaner is unavailable, another cleaning solution is two tablespoons of baking soda mixed with two tablespoons of water.

You’ll also want to check for any damaged or frayed cables and replace them if needed.

STEP 5: Install the New Battery

Now, it’s time to install the new battery. To properly do this, you want to make sure to align the positive and negative ends of the new battery with the matching terminals. Lower the new battery into the battery tray and refasten the metal bolt or bar.

Then, you’ll want to replace and tighten the battery clamps. Connect:

  • First, the positive cable to the battery (+)
  • Second, the negative cable to the battery (-)

When installing the new battery, it’s important to connect the positive cable first. Once you’ve properly installed the new battery, you can close the hood and start the car!


BMW of Stratham Can Help Change Your Car Battery

When the time comes for drivers around Stratham, Portsmouth, and Exeter, NH, to change their car battery, the steps outlined above can be a helpful guide through the process. Our BMW Stratham service center team is always here to provide additional help or to answer any questions, so don’t hesitate to reach out!